Some business entities' income tax returns have due dates other than April 15. The instructions for each type of form used will note the appropriate due date(s):

• A sole proprietor's Schedule C (Form 1040), Profit or Loss From Business (Sole Proprietorship) and an individual farmer's Schedule F (Form 1040), Profit or Loss From Farming for income and expenses are attached to the Form 1040, U.S. Individual Income Tax Return or Form 1040-SR, U.S. Tax Return for Seniors. Therefore, the due date is the 15th day of the fourth month following the end of the tax year. This is generally April 15 for calendar year taxpayers.
• Most partnerships use the calendar year. The partnership tax return is generally due by the 15th day of the third month following the end of the tax year. See the Instructions for Form 1065, U.S. Return of Partnership Income.
• An S corporation generally must use the calendar year unless the entity can establish a business purpose for having a different tax year. The due date is the 15th day of the third month following the end of the tax year. See the Instructions for Form 1120-S, U.S. Income Tax Return for an S Corporation.
• A corporation that's not an S corporation may use either the calendar year or a fiscal tax year. The corporate tax return is generally due by the 15th day of the fourth month following the end of the corporation's tax year. See the Instructions for Form 1120, U.S. Corporation Income Tax Return for due dates and exceptions to due dates.

Note: For any due date that falls on a weekend or legal holiday, the due date is extended to the next business day.